Charcoal briquettes are commonly used in the United States as a source of heat and flavor for outdoor cooking on a barbecue grill or hibachi. The charcoal briquettes are formed from a combination of a combustible carbonaceous material such as charcoal, pete, coal, or other combustible carbon sources together with a binder, such as corn starch, a non-toxic polymeric material and the like, compressed under high pressure into briquettes for use as a barbecue fuel. After the composition is formed into a briquette, the briquettes are dried to remove essentially all of the moisture so that the briquettes are capable of ignition. Exemplary of various charcoal briquette compositions and methods of manufacturing charcoal briquettes include the following U.S. Pat. Nos.: Spencer, 1,590,706; Wagel, 1,618,029; Jaffe, 3,089,760; McGoff, 3,304,161; Ross, 3,709,700; Robertson, 3,485,600; Mennen, 3,385,681; Onozawa, 3,689,234; Swinehart, et al 2,822,251; Hughes, et al 4,167,398; and, Crace, 4,787,914.
Many charcoal briquettes presently are manufactured using corn starch as the sole binder for maintaining the briquette in the form of a cohesive mass having sufficient green strength and dry strength so that the briquette does not break into pieces during normal transportation, storage and handling. While others have attempted to eliminate some of the corn starch binder by replacing this binder with other additives, in order to increase the binding strength or to reduce the cost of manufacturing the charcoal briquettes, these attempts, in the past, have not met with much success because of the inability of the binder combination to provide adequate green strength and dry strength to the finished charcoal briquettes and the inability of such binder combinations to provide a smooth briquette surface which, in the consumer's eye, is an indication of quality.
These disadvantages have been overcome in accordance with the principals of the present invention by providing a binder mixture for a combustible carbonaceous material in the formation of a charcoal briquette that includes an organic binder together with a water-swellable clay, in a weight ratio of about 1.5 to about 3.0 parts by weight organic binder to 1 part by weight water-swellable clay, and forming a water slurry of the organic binder and the water-swellable clay to achieve tenacious physical and/or chemical bonding between the water-swellable clay and the organic binder prior to mixing the binder composition with the combustible carbonaceous material.